Since its inception in 1972 the biennial Gordon Research Conference on Microbial Toxins and Pathogenicity has formed a prime focal point for researchers studying microbial pathogenicity and related subjects. Recent advances in understanding the the modes of action of action of known toxins at the molecular level, the identification of new toxins and virulence factors, and the possibility of applying knowledge of toxin structure and activity to the construction of targeted cytotoxic agents (with potential applications in cancer chemotherapy), have made this area one of the most exciting in modern biology. The 1982 Conference will focus on membrane interactions of microbial proteins; sessions are planned on toxin entry into host cells, viral entry mechanisms, targeting of toxins, colicins as models of toxin action, and bacterial adhesion to mammalian cell surfaces. Other sessions will be held on the genetics of virulence, colostridial neurotoxins, and selected topics in microbial pathogenicity. Poster sessions will complement the plenary sessions.